Trisazo-dyestuffs



TRISAZO-DYESTUFFS Raymond Gunst, Binningen, Switzerland, assignor to Ciba Limited, Basel, fiwitzerland, a Swiss .No Drawing. ApplicationMay19,1952, Serial No. 288,753

The present invention provides new trisazo dyestufis, for example, the dyestuff of the formula HQIS United States Patent HO NH:

in which R1 represents an aromatic radical of the benzene series containing at least one sulfonic acid group, and X represents a diazotized amino group, with a hydroxynaphthalene sulfonic acid free from substituents other than the hydroxyl group and the sulfonic acid group or groups, and by so choosing the starting materials that the total number of sulfonic acid groups present in the radical R1 andinthe hydroxynaphthalene sulfonic acid is at leastthree.

The diazo-azo-compounds of the Formula 3, certain of which are known, can be made by coupling tetra-j zotized 4:4'-diaminodiphenyl in an acid medium on .one side with 1-amino-8-hydroxynaphthalene-3:6-disulfonic acid, and then coupling the resulting compound in an alkaline medium with the diazo compound of an amine of the formula R1-NH2, in which R1 has the meaning given above.

As amines of the formula R1--NH2 there come into consideration aniline sulfonic acids such as aniline-2- or -3-"or especially -4-sulfonic acid, or aniline disulfonic acids such as aniline-3:5- or -2:5-disulfonic acid.

Coupling of the tetrazotized 4:4-diaminodiphenyl 2,731,459 Patented Jan. 17, 19 56 with the 1-amino-8-hydroxynaphthalene-3zfi-disulfonic acid is carried out in an acid medium, advantageously a medium rendered acid with a mineral acid. For coupling the resulting diazo-monoazo-compound with the diazo compound of the amine of the formula R-NH2 in an alkaline medium there is advantageously used a medium rendered alkaline with an alkali carbonate.

As will be apparent from what has been stated above, there may be used as starting materials hydroxynaphthalene monosulfonic acids, provided that the radical R1 of the diazo-azo-compound contains two sulfonic acid groups. If, however, the latter radical contains only a single sulfonic acid group it is necessary to use as a coupling component a hydroxynaphthalene sulfonic acid containing at least two sulfonic acid groups. Taking into account what has been stated above there come into con- HO SOaH dOaH sideration as hydroxynaphthalene sulfonic acids, for example,

l-hydroxynaphthalene-4- or S-sulfonic acid, 2-hydroxynaphthalene-6- or-7-sulfonic acid, l-hydroxynaphthalene-3:6-, -3:8- or -4:8-disulfonic acid,

and 2-hydroxynaphthalene-3:6- or -3:8-disulfonic acid.

The coupling of the diazo-azo-compounds of the Formula 3 with the hydroxynaphthalene sulfonic acids is advantageously carried out in an alkaline medium.

The dyestufis of the invention are new and correspond to the above Formula 2. As follows from the above explanations, these dyestuifs contain at least five and preferably not more than six sulfonic acid groups. Especially valuable products are the dyestufis containing five sulfonic acid groups, for example, those which contain a single sulfonic acid group in the radical R1 and two sulfonic acid groups in the radical R2. The dyestutfsof the Formula 2 are principally suitable for dyeing chrometanned leather, especially velour leather (suede). The dyeings are distinguished by their good fastness to light and also by their especially desirable navy blue tints, and by the fact that as compared with leather dyestuffs of similar constitution they do not exhibit the bronzing eifect which frequently occurs and is very undesirable. Moreover, the dyestuffs possess the advantage that the coupling components (hydroxynaphthalene sulfonic acids) required in making them are easily accessible compounds.

The following examples illustrate the invention, the parts and percentages being by weight:

Example 1 I is separated by filtration and dried. The resulting black 'leather, especially velour leather, reddish navy blue tints.

. phenyl and 1-amino-8-hydroxynaphthalene-3:fi-disulfonic .1 V 2,731,459 a I I a throughout. Aiter 12 hours, there is run in at 50 C. a known manner. A clear solution of 34.1 parts of 1- diazonium solution prepared from 1 7 .3 parts of l aminoamino-8hydroxynaphthalene-El:6 disulfonic acid in 300 g t mfl ac1d, and. 3 5011mm of 26 Parts of parts of water, having a pH value of 5.6 is introduced ium car onate in 120 parts of water is poured into the i couplingmixmre p y while stirring vigorously. The dropwise into the tetrazo solution in the course of one pH value'must not be higher than 8.5. After30 minutes there'is added'a solution of 30.4 parts of Z-hydroxynaphthalenea.zr6 disulfonic acid and parts of Sodium bonate the mineral ac1d liberated during coupling is neue b t i 150 parts of t Af irri for 2 tralized so as to maintain the reaction of the mixture dishours the reaction mixture is rendered weakly acid by 10 tinctlyacid to Congo. After 12 hours, a diazonium soluthe addition of hydrochloric acid, the precipitated dyetion prepared from 25.3 parts of l-aminobenzne-ZzS-distuff of the formula sulfonic acid is run in at 5 C., and a solution of 26 parts H O NHa H (i) S O :11

ducing dropwise a dilute aqueous solution of sodium carpowder dissolves easily in water, and dyes chrome tanned so mm c r em e m 2 par S of Water 1s m reduced ously. The pH value should not be higher than 8.5.

After 30 minutes a solution of 22.4 parts of 2-hydroxynaphthalene-6-sulfonic acid and 5 parts of sodium carbonate in 150 parts of water is added. After stirring for By using for the last coupling l-hydroxynaphthalene- 3:6-disulfonic acid, instead of 2-hydroxynaphthalene- 3:6-disulfonic acid, a very similar dyestuff is obtained which corresponds to the formula H0 NH: HO

HOaS SOIH HOsS- --SO;H

' Example 2 2 hours the reaction mixture is rendered weakly acid by By the procedure described in Example 1 an interthe addition of hydrochloric acid, and the precipitated mediate compound is prepared from 4':4'-dia.minodi- I acid and coupled with l-diazobenzene-4-sulfonic acid. 40 I d 11 1 1 f 11 In a manner analogous to that described in Example 1 gigg zi Rather espcla y 6 F navy the product is finally coupled with l-hydroxynaphthaleney g. instead of 2 hydroxynaphthalenesulfonic 4:8-disulfonic acid. The dyestuif so obtained correv sponds tothe formula acid in the final coupling, 1-hydroxynaphthalene-4-sul 110 NH; HO sou;

It isof excellent solubility, and dyes velour leather handfonic acid a very similar dyestufl? is obtained which prosome navy blue tints. I

A similar dyestuff of excellent solubility is obtained by using,. instead of l-aminobenzene-4-sulfonic acid, an V v 7 equivalent quantity'of' l-aminobenz'ene-Z:5-disulfonic acid 100' parts of well fulled velour leather. are worked in a or 1-aminobenz'ene-3:S-disulfonic acid. dyeing vessel with 8' times the amount of water at C.

By using instead of 1-hydroxynaphthalene-4:8 disul- 5 parts of the dyestutf obtainable as described in t'h'e first' ionic acid, Z-hydroxynaphthalene-6:8-disulfonic acid a paragraph of Example 1 dissolved in 50 parts of water are similar dyestulf is obtained, which corresponds to the foradded, and dyeing is carried on for one hour. Fixation mula T is carried out b'ythe'additio'n of 5 parts'of formic acid to Example 4 and yields somewhat more greenish navy blue tints on I h minutes-. The" quantities are calculated on the dry weight Example 3 of th leather. There is obtained a full reddish navy 19' 6f 4z4'-diaminodipheiiyl are tetraz'otized in" blue dyeing.

5 hour. The temperature is 10-l5 C. By slowly introrapidly into .the coupling mixture while stirring 'vigordyestufi is separated by filtration and dried. The black 7 powder so obtained dissolves easily in water and dyes 5 duces on chrome leather somewhat more reddish dyeings thedye-liquor and the leather is worked for a further 30" 6 What is claimed is: 3. A trisazo-dyestufi which corresponds to the formula HO NH:

HOsS

HOaS 80311 1. A trisazo-dyestuif which corresponds to the formula in which R2 represents an aromatic radical of the naph- HO NH: 10 thalene series of the composition 1 in which R1 represents a benzene radical, R2 represents 4. A trisazo-dyestufl which corresponds to the formula HOsS- SOaH H? NHs the radical of a mono-hydroxynaphthalene, each of the in which R2 represents an aromatic radical of the naphradicals R1 and R2 contains at least one sulfonic acid thalene series of the composition group, the two radicals R1 and R2 together contain at least three sulfonic acid groups, and the hydroxy group r -0H and sulfonic acid groups are the single substituents present in the radical Ra. I (so H) J a 2 5. The trisazo-dycstuff which corresponds to the formula H0 NH: HO

H0i8- 808E H088 80211 6. The trisazo-dyestutf which corresponds to the formula HO NH: HQ :11

HO: 2. A msazo-dyestufi which corresponds to the formula 5 HO NH:

7. The trisazo-dyestufi which corresponds to the forin which R1 represents a benzene radical substituted by m mula HO NH: HO

HO| OsH H015 sulfonic acid groups and R2 represents an aromatic radical of the naphthalene series of the composition References Cited in the file of this patent T 10 UNITED STATES PATENTS T 2,073,000 Clingestein et a1. Mar. 9, 1931 L om 2,157,295 Lier May 9, 1939 m and it each representing a whole number of at most 2 FOREIGN PATENTS and the sum m+n being at least 3 and at the most 4. (5 153,557 Germany Apr. 2, 1901 

1. A TRISAZO-DYESTUFF WHICH CORRESPONDS TO THE FORMULA 